BEIJING—Southern China and Vietnam are bracing for the arrival of Typhoon Rammasun after the massive storm killed at least 38 people in the Philippines.

The official Xinhua News Agency said Rammasun had winds of up to 180 kph (112 mph). It was due to hit land late Friday on Hainan island off the southern China coast and Guangdong province. State media said it might become the strongest typhoon to hit Hainan in 40 years.

The typhoon was also set to plow through northern Vietnam and bring high wind and rain to Hong Kong.

Rammasun barrelled through the northern Philippines on Wednesday, drenching the capital of Manila. The deadly typhoon forced the evacuation of half a million people and knocked out power to whole provinces.